Study Shows CABG Mortality Better Than PCI

In short

theheart.org tells us about a comparative effectiveness study between CABG surgery and Percutaneous Coronary Intervention (PCI) in a matched population of real-world patients and providers. The data suggests CABG surgery is associated with an overall 8% lower risk of death compared with PCI. However disease status does influence the gap between the treatment modalities, concomitant diseases mostly lowering the disparity.

Background

The study has been published this week in the Annals of Internal Medicine and details an observational comparison of 105,156 propensity score-matched Medicare patients. The baseline clinical characteristics of the matched patients were similar between patients who received CABG and those who received PCI. The average patient, according to the researchers, was 75 years old, white, had hypertension, and was followed for a median of 4.3 years.

The survival rate after five years was 74.1% for CABG and 71.9% for PCI, a difference that translated into a statistically significant all-cause mortality hazard ratio [HR] of 0.92 (95% CI 0.90-0.95). The interaction with race and treatment was due to the inclusion of “other races,” report the researchers, as there was no interaction between mortality and treatment among white and black patients.

The reduction in mortality with CABG was significantly lower among patients with diabetes, a history of tobacco use, heart failure, and peripheral artery disease, providing strong evidence that clinical characteristics modify the CABG-PCI treatment effect.

Investigator comments

Based on individualized predictions of survival in the five-year period postrevascularization, the researchers say that approximately 0.053 life-years would be gained if patients were treated with surgery rather than PCI. “The number of life-years added by CABG over five years is an underestimate of the lifetime effect of treatment, because the CABG and PCI survival curves are separated for up to 10 years and subsequent follow-up is limited,” write Hlatky and colleagues.

These results, according to the researchers, are in line with a previous analysis of 10 randomized trials and other trials. “This body of evidence suggests that the use of CABG rather than PCI is likely to reduce mortality for the average patient with multivessel coronary disease,” write Dr Mark Hlatky (Stanford University School of Medicine, CA) and colleagues.